Centering device for conductor tube for GMAW manual/robotic arc welding MIG guns

ABSTRACT

An arc welding apparatus is disclosed in one form including a conductor tube defining an internal passageway and a distal end portion. The internal passageway has an internal profile proximate the distal end portion. The apparatus further includes an alignment device comprising an exterior profile and an internal passage. The exterior profile is configured for mechanical attachment to the internal profile of the conductor tube. The apparatus also includes a conduit liner disposed in the internal passageway of the conductor tube and the internal passage of the alignment device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non provisional of U.S. Application No.61/559,111, filed on Nov. 13, 2011. The disclosures of the aboveapplication are incorporated herein by reference.

FIELD

The present disclosure relates generally to welding apparatuses, andmore particularly to arc welding apparatuses such as Metal Insert Gas(MIG) or Gas Metal Arc Welding (GMAW) welding guns including consumablesfor generating welding arc and diffusing shield gas.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

In an arc welding apparatus, such as Metal Insert Gas (MIG) or Gas MetalArc Welding (GMAW) welding gun, a welding wire is fed through thewelding gun to provide a molten metal pool to join metal workpiecestogether. An inert gas is directed through the front (distal) end of thewelding gun to provide a surrounding layer or blanket of shielding gasto protect the molten metal pool from atmospheric contamination. Theinert gas is typically a combination of various gases such as argon orhelium, among others.

A prior art MIG or GMAW welding gun typically includes a contact tip anda gas diffuser connected to the contact tip. The contact tip has acentral bore to guide the welding wire to the workpieces. The contacttip transfers electrical current to the welding wire. The gas diffuseris threaded to the contact tip and defines gas passageways to direct theshielding gas into forming the blanket of shielding gas around themolten metal pool. The contact tip and gas diffuser are constantlysubjected to high heat and are susceptible to wear due to hightemperature operation.

SUMMARY

The present disclosure generally provides a centering device for an arcwelding apparatus, such as an MIG or GMAW welding gun to align a conduitliner with the exit orifice of a contact tip. The various forms of thepresent disclosure provide a simplified structure and improvedoperation.

In one form, an arc welding apparatus includes a conductor tube definingan internal passageway and a distal end portion. The internal passagewayhas an internal profile proximate the distal end portion. The apparatusfurther includes an alignment device comprising an exterior profile andan internal passage. The exterior profile is configured for mechanicalattachment to the internal profile of the conductor tube. The apparatusalso includes a conduit liner disposed in the internal passageway of theconductor tube and the internal passage of the alignment device. Theconduit liner terminates near the proximal end portion of the conductortube.

In another form, an arc welding apparatus includes a conductor tubedefining an internal passageway and a distal end. The internalpassageway has an internal profile configured for mechanical attachmentto the exterior profile of an alignment device having a proximal end anda distal end. In one form, the alignment device is pressed into theconductor tube and centers a conduit liner with the exit orifice of acontact tip.

In still another form, an alignment device for use in a weldingapparatus comprising an exterior profile being configured for mechanicalattachment and an internal passage, wherein the alignment device alignsa conduit liner with an exit orifice of a contact tip.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a side view of an arc welding apparatus including a contacttip-diffuser constructed in accordance with the teachings of the presentdisclosure;

FIG. 2 is a cross-sectional perspective view of a consumable assemblyconnected to a conductor tube and having a contact tip-diffuserconstructed in accordance with a first embodiment of the presentdisclosure;

FIG. 3 is a partial exploded, perspective view of a conductor tube and aconsumable assembly constructed in accordance with a first embodimentthe present disclosure;

FIG. 4 is a partial exploded, cross-sectional view of a conductor tubeand a consumable assembly constructed in accordance with a firstembodiment of the present disclosure;

FIG. 5 is a cross-sectional view of a contact tip-diffuser constructedin accordance with a first embodiment of the present disclosure;

FIG. 6 is a cross-sectional view of a variant form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 7 is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 8 is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 9 is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 10 is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 11 is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 12 is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure;

FIG. 13A is a cross-sectional view of another form of a contacttip-diffuser constructed in accordance with a first embodiment of thepresent disclosure, FIG. 13B is a cross-sectional view of a contact tipdiffuser, and 13C is a curve representing the relationship between thetip bore length and the tip inside diameter;

FIG. 14 is a cross-sectional, perspective view of an inner body of anozzle constructed in accordance with a first embodiment of the presentdisclosure;

FIG. 15 is a cross-sectional view of a consumable assembly and aconductor tube of the arc welding apparatus constructed in accordancewith a first embodiment of the present disclosure;

FIG. 16 is a cross-sectional view of a consumable assembly and aconductor tube of an arc welding apparatus constructed in accordancewith a second embodiment of the present disclosure;

FIG. 17 is a partial exploded view of a consumable assembly and aconductor tube of an arc welding apparatus constructed in accordancewith a third embodiment of the present disclosure; and

FIG. 18 is a cross-sectional view of a consumable assembly and aconductor tube of an arc welding apparatus constructed in accordancewith a third embodiment of the present disclosure;

FIG. 19A is a profile and cross-sectional view of the conductor tube ofan arc welding apparatus constructed in accordance with an embodiment ofthe present disclosure, and FIG. 19B is a profile and cross-sectionalview of the conductor tube of an arc welding apparatus constructed inaccordance with another embodiment of the present disclosure;

FIG. 20A is a partially exploded profile and cross-sectional view of anarc welding apparatus constructed in accordance with a third embodimentof the present disclosure, and FIG. 20B is a detailed view of anembodiment of the centering device constructed in accordance with athird embodiment of the present disclosure;

FIG. 21A is a partially exploded profile view of the conductor tube andadaptor sleeve of an arc welding apparatus constructed in accordancewith a third embodiment of the present disclosure, and FIG. 21B is apartially exploded cross-sectional view of the conductor tube andadaptor sleeve of an arc welding apparatus constructed in accordancewith a third embodiment of the present disclosure;

FIG. 22 is a perspective view of a contact tip-diffuser of a consumableassembly constructed in accordance with a fourth embodiment of thepresent disclosure;

FIG. 23 is a cross-sectional view of a consumable assembly and aconductor tube constructed in accordance with a fifth embodiment of thepresent disclosure;

FIG. 24 is a cross-sectional view of a consumable assembly and aconductor tube constructed in accordance with a fifth embodiment of thepresent disclosure;

FIG. 25 is an enlarged view of FIG. 24, showing the interface betweenthe contact tip-diffuser and the conductor tube;

FIG. 26 is a perspective view of a consumable assembly and a conductortube constructed in accordance with a sixth embodiment of the presentdisclosure;

FIG. 27 is a partial exploded, cross-sectional and perspective view of aconsumable assembly and a conductor tube constructed in accordance witha sixth embodiment of the present disclosure;

FIG. 28 is a partial exploded perspective view and partial explodedcross-sectional view of a consumable assembly and a conductor tubeconstructed in accordance with a seventh embodiment of the presentdisclosure;

FIG. 29 is a partial exploded perspective view of a consumable assemblyand a conductor tube constructed in accordance with a seventh embodimentof the present disclosure;

FIG. 30 is a cross-sectional view of a consumable assembly and aconductor tube constructed in accordance with a seventh embodiment ofthe present disclosure;

FIG. 31A is a detail view of a conductor tube and a sleeve constructedin accordance with a seventh embodiment of the present disclosure andFIG. 31B is a detail view conductor tube and sleeve demonstrating analternate conductor tube and sleeve related to the seventh embodiment ofthe present disclosure;

FIG. 32 is perspective view and a partial exploded perspective view of aconsumable assembly and a conductor tube constructed demonstrating analternate conductor tube and sleeve related to the seventh embodiment ofthe present disclosure; and

FIG. 33A is a detail view of an alignment device constructed inaccordance with a seventh embodiment of the present disclosure and FIGS.33B and 33C are detail views of alignment devices demonstratingalternate conductor configurations related to the seventh embodiment ofthe present disclosure.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no wayintended to limit the present disclosure or its application or uses. Itshould be understood that throughout the description and drawings,corresponding reference numerals indicate like or corresponding partsand features. And although the term “MIG” or “GMAW” is used throughoutthe specification, it should be understood that the teachings of thepresent disclosure apply to any type of welding gun.

Referring to FIG. 1, an arc welding apparatus, such as a MIG or GMAWwelding gun, is illustrated and generally indicated by reference numeral10. The MIG welding gun 10 includes a handle 12, a conductor tube 14attached to the handle 12, and a consumable assembly 16 attached to theconductor tube 14. The handle 12 is connected to a welding cable 18 thatcarries welding current, shielding gas, and a welding wire 20 from apower source (not shown), a gas source (not shown), and a wire feeder(not shown) to the welding gun 10.

The consumable assembly 16 includes a plurality of consumable componentsand generally includes a nozzle 22 and a contact tip-diffuser 24disposed inside the nozzle 22 according to a first embodiment of thepresent disclosure. The structure and operation of the arc weldingapparatus has been disclosed in U.S. Pat. Nos. 5,491,321 and 5,338,917,which are commonly owned by the assignee of the present application, andthe contents of which are incorporated herein by reference in theirentirety.

Referring to FIGS. 2 through 4, the consumable assembly 16 is connectedto a distal end portion 26 of the conductor tube 14. The nozzle 22 issubstantially cylindrical and receives the distal end portion 26 of theconductor tube 14 therein. The contact tip-diffuser 24 is coaxiallydisposed inside the nozzle 22 and has a portion inserted into the distalend portion 26 of the conductor tube 14. The conductor tube 14 includesa cylindrical conductor body 28 defining an internal passageway 30, anda conduit liner 32 disposed in the internal passageway 30. The conduitliner 32 has a guiding channel 34 for guiding the welding wire 20 fromthe welding cable 18 and the handle 12 to the contact tip-diffuser 24.

The nozzle 22 includes an outer body 90, an insulator 92 and an innerbody 94, which are integrally formed as a single integrated unit. Theinsulator 92 is disposed between the outer body 90 and the inner body 94for insulating the inner body 94 from the outer body 90. The nozzle 22is disposed around the integrated tip-diffuser 24 and secured to thedistal end portion 26 of the conductor tube 14. The distal end portion26 of the conductor tube 14 defines an internal tapered surface 66, anexternal shoulder 80, and an outer contact surface 82 proximate theexternal shoulder.

The contact tip-diffuser 24 has an integrated structure and functions asboth a contact tip for transferring electrical current and a gasdiffuser for diffusing shielding gas. The contact tip-diffuser 24includes a hollow cylindrical body 36 defining an internal cavity 38 andan exit orifice 40 open to and aligned with the internal cavity 38. Theinternal cavity 38 and the exit orifice 40 jointly extend the entirelength of the contact tip-diffuser 24. The internal cavity 38 of thecontact tip-diffuser 24 is aligned with the internal passageway 30 ofthe conductor tube 14 such that the conduit liner 32 of the conductortube 14 can extend into the internal cavity 38 of the contacttip-diffuser 24. In one example, the cylindrical body 36 of the contacttip-diffuser 24 is made of a copper alloy, such as C18200, C181500 orC12200DHP and can be produced by machining or other large volumemanufacturing processes such as cold forming, extruding or thecombination of the two.

As clearly shown in FIG. 5, the contact tip-diffuser 24 includes thecylindrical body 36 defining a proximal end portion 44 proximate theconductor tube 14 and a distal end portion 46 proximate the workpieces.The internal cavity 38 extends from the proximal end portion 44 to thedistal end portion 46 and is substantially cylindrical. The cylindricalbody 36 further includes an outer wall 50, an outer shoulder 52 disposedat the proximal end portion 44, and an inner shoulder 53 disposed nearthe distal end portion 46 of the cylindrical body 36. The inner shoulder53 is also disposed at a distal end 47 of the internal cavity 38 andprovides a stop for the conduit liner 32 of the conductor tube 14.

A plurality of apertures 54 extend through the outer wall 50 of thecylindrical body 36 into the internal cavity 38 and are located betweenthe proximal end portion 44 and the distal end portion 46. In thepresent embodiment, four apertures 54 (only three are shown) extendnormally (e.g. perpendicularly) through the outer wall 50 of thecylindrical body 36 and are spaced at 90°. It is understood that anynumber of apertures can be formed through the outer wall 50 of thecontact tip-diffuser 24 without departing from the scope of the presentdisclosure. During operation, the shielding gas is directed from theinternal passageway 30 of the conductor tube 14 into the internal cavity38 of the contact tip-diffuser 24. The shielding gas is then directedoutside the contact tip-diffuser 24 through the plurality of apertures54 to form a blanket of shielding gas surrounding the contacttip-diffuser 24 and between the contact tip-diffuser 24 and the nozzle22. The blanket of shielding gas protects the molten metal pool duringoperation.

By directing the shielding gas from inside the contact tip-diffuser 24to outside the contact tip-diffuser 24 and making the shielding gas indirect contact with the contact tip-diffuser, the contact tip-diffuser24 can be more efficiently cooled by the shielding gas. Heat transferfrom the contact tip-diffuser 24 to the shielding gas can be achievedvia thermal conduction and convection, as opposed to thermal radiationor convection in the prior art arc welding apparatuses where theshielding gas does not flow through the contact tip. Moreover, accordingto the present disclosure, the shielding gas provides cooling bothinside and outside the contact tip-diffuser 24 and thus can more quicklyremove heat from the contact tip-diffuser 24.

The exit orifice 40 extends through the distal end portion 46 of thecylindrical body 36 and has a length L1, which is approximately fourtimes the size (e.g., the diameter D1) of the opening of the exitorifice 40. In the present embodiment, the exit orifice 40 is centeredalong a centerline C of the cylindrical body 36. The exit orifice 40defines a radiused inlet 60. The radiused inlet 60 reduces scraping andshaving of the welding wire 20 when the welding wire 20 moves throughthe exit orifice 40. The length L1 of the exit orifice 40 is madesmaller than that of the exit orifice in a prior art contact tip toprovide controlled contact between the welding wire 20 and the contacttip-diffuser 24 for improved arc stability and less chance of exitorifice obstruction. Moreover, the smaller length of the exit orifice 40reduces friction surface between the welding wire 20 and the contacttip-diffuser 24.

An external contact surface 64 is disposed around the proximal endportion 44 of the cylindrical body 36 and defines a taper configured toabut a corresponding internal tapered surface 66 (shown in FIGS. 2 and4) of the conductor tube 14, which will be described in more detailbelow. The external contact surface 64 is tapered outwardly from theproximal end portion 44 towards the distal end portion 46.

FIGS. 6 to 13 refer to various embodiments of the contact tip diffusersimilar to that of FIG. 3. Referring to FIGS. 6 and 7, another form of acontact tip-diffuser 68 is similar to that of FIG. 3 except for theorientation of the apertures. In the example of FIG. 6, a contacttip-diffuser 68 defines a plurality of apertures 70 extending at anangle through the outer wall 50 of the cylindrical body 36. In theexample of FIG. 7, a contact tip-diffuser 69 has a plurality ofapertures 71 each having an inlet 73, an axial passage 75, and an outlet77. The axial passage 75 extends along a longitudinal direction of thecontact tip-diffuser 69 and connects the inlet 73 open to the internalcavity 38 to the outlet 77 formed on an exterior portion 79 of the outerwall 50.

Referring to FIG. 8, another form of a contact tip-diffuser 72 issimilar to that of FIG. 3, except for the configuration of the exitorifice. The contact tip-diffuser 72 defines an exit orifice 74 that isoffset from the centerline C of the cylindrical body 36. The exitorifice 74 generally defines a wave shape to create a plurality ofcontact points 76. The wave shape may be significantly sinusoidal orhave increasing or decreasing wavelengths along the length of passageextending toward the exit orifice. When the welding wire 20 movesthrough the exit orifice 74, the welding wire 20 contacts the pluralityof contact points 76, which improve contact between the welding wire 20and the contact tip-diffuser 24, thereby providing stable currenttransfer from the contact tip-diffuser 24 to the welding wire 20.

Referring to FIGS. 9 through 12, other variations of contacttip-diffusers 84 a to 84 d are similar to that of FIG. 3 except for theplurality of apertures 54 are defined various forms and orientations ofa plurality of slots 84 e to 84 h. As used herein, the term slot shallbe construed to mean an aperture or opening defining a geometry having alength greater than or equal to a width in a substantially rectangularform.

In the example of FIG. 9, a contact tip-diffuser 84 a defines aplurality of slots 84 e, having a length and width, the length beinglonger than the width across a symmetric axis of the slot 84 e. Thelength of the each slot 84 e may extend at an angle perpendicular to thelongitudinal axis 84 i of the cylindrical body 36. The plurality ofslots 84 e may be defined as a plurality of polygonal openings 84 jsignificantly square in shape that promote more consistent shielding gasflow and coverage. In the example of FIG. 10, a contact tip diffuser 84b has a plurality of slots 84 f, the length of each slot extendingparallel to the longitudinal axis 84 i. Each slot may have asignificantly rounded profile 84 k about two ends. Further, in thisexample the slots are formed at an angle in relation to the outer wall50 of the cylindrical body 36 causing the shielding gas to be directedrotationally in the nozzle 22. The angle in relation to the outer wall50 is shown having an acute side extending axially; however the acuteside may extend longitudinally or at an intermediate position betweenthe radial and longitudinal axis.

Referring now to FIG. 11, a contact tip diffuser 84 c is shown havingplurality of slots 84 g each having a length extending parallel to thelongitudinal axis 84 i and each slot is shown having a rounded internalpassage wall 84 l. The internal passage wall 84 l of each slot may alsocomprise chamfers, fillets or other variations and combinations thereofto optimize the flow of the shielding gas. In FIG. 12 another example ofa contact tip diffuser 84 d has plurality of slots 84 h each extendingat an angle in relation to the longitudinal axis 84 i.

In the example of FIG. 13A, a contact tip-diffuser 86 a defines aplurality of slots 86 b and a plurality of holes 86 c extending throughthe outer wall 50 of the cylindrical body 36. In this example, theplurality of slots 86 b is evenly spaced radially in relation to thelongitudinal axis 84 i and forms a row of slots 86 d. Further theplurality of holes 86 c is evenly spaced radially about the longitudinalaxis and forms a row of holes 86 e. Each hole 86 d and each slot 86 calso alternate about the outer wall 50 of the cylindrical body 36. Thisexample of the contact tip diffuser further demonstrates the differentimplementations of the plurality of apertures 54 introduced in all ofthe previous figures.

Referring to FIGS. 13B and 13C, FIG. 13B demonstrates a cross-sectionalview of a contact tip diffuser, and FIG. 13C demonstrates a curverepresenting the relationship between the bore length 88 a and the tipinside diameter (I.D.) 88 b of the contact tip diffuser 84 a. The borelength 88 a represents the length of the contact tip diffuser 84 a thatcontacts the welding wire extending from the distal end portion 46 tothe radiused inlet 60. The tip inside diameter 88 b represents thediameter of the cylindrical exit orifice 40. The curve 88 c illustratesthe ratio between the bore length 88 a and the tip inside diameter 88 bof the exit orifice 40 for the contact tip diffuser 84 a and othercontact tip diffuser contemplated by the disclosure.

The curve 88 c demonstrates that for smaller welding wires and tipinside diameters 88 b, the bore length ratio 88 d may be higher. Forexample, when the tip inside diameter 88 b is 7/64 in., the bore lengthratio is between 3 and 4, but when the tip inside diameter 88 b is0.045, the bore length ratio 88 d is between 6 and 7. In general, thebore length ratio 88 d may be between 2 and 9 for contact tips havingtip inside diameters between ⅛ in. and 0.035 in. respectively. FIG. 13Cillustrates guidelines for implementing the contact tip diffusersdisclosed and should not be considered limiting to the scope of thedisclosure. The curve 88 c demonstrates that the bore length ratio 88 dincreases as the tip inside diameter 88 b decreases for contact tipdiffusers.

The implementations of the contact tips shown are only exemplary andshould not be considered limiting this disclosure. Other examples mayinclude multiple rows comprising a plurality of slots, a plurality ofholes or any combination thereof further comprising a plurality of gasoutlet passages from the cavity 38. The gas outlet passages may beformed symmetrically or a-symmetrically in relation to one another andthe individual placement of the each outlet passage about the body. Thegas outlet passages may be formed in any pattern extending around thecircumference of the body and may also comprise rows extending at anglesradially about the body with respect to the longitudinal axis 84 i.

In yet another implementation a row of holes and a row of slots mayoverlap or a plurality of slots may comprise individual slots eachextending lengthwise at a different angles with respect to thelongitudinal axis. Finally the gas outlet passages may comprisedifferent shapes including but not limited to ellipses and polygonshaving a variety of chamfered or filleted sides or edges. Each of theprevious examples demonstrates an implementation of gas outlet passagesthat direct shielding gas into the nozzle 22 and provide for improvedcooling of the contact tip diffuser 24 while maintaining shielding gascoverage for improved contact tip life for implementations in accordancewith this disclosure.

Referring to FIG. 14, the inner body 94 of the nozzle 22 is configuredto function as a tip holder and secure the integrated tip-diffuser 24therein. The inner body 94 includes a generally cylindrical hollow body76 and includes a proximal end 100 and a distal end 102. The inner body94 defines an internal distal flange 96 at the distal end portion 102,and an intermediate flange 104 between the proximal end portion 100 andthe distal end portion 102. The internal distal flange 96 defines aperipheral angled surface 106 for contacting the external shoulder 52 ofthe contact tip-diffuser 24. The intermediate flange 104 defines aninner peripheral contact surface 108. The internal distal flange 96abuts the external shoulder 52 of the contact tip-diffuser 24 to secureand position the integrated tip-diffuser 24.

Referring to FIG. 15, when the conductor tube 14 and the contacttip-diffuser 24 are inserted into the nozzle 22, the inner peripheralcontact surface 108 of the inner body 94 contacts the outer contactsurface 82 of the conductor tube 14 and the external shoulder 80 of theconductor tube 14 engages the intermediate flange 104 of the inner body94. The angled surface 106 of the internal distal flange 96 of the innerbody 94 contacts the outer shoulder 52 of the contact tip-diffuser 24and prevents the contact tip-diffuser 24 from moving distally asindicated by arrow X. The contact tip-diffuser 24 is prevented frommoving proximally as indicated by arrow Y by the internal taperedsurface 66 of the conductor tube 14. The external contact surface 64 ofthe contact tip-diffuser 24 is configured to match the internal taperedsurface 66 of the conductor tube 14 such that when the proximal endportion 44 of the contact tip-diffuser 24 is secured to the distal endportion 26 of the conductor tube 14, the external contact surface 64 ofthe contact tip-diffuser 24 is in close contact with the internaltapered surface 66 of the conductor tube 14.

Sufficient physical contact is provided between the external contactsurface 64 of the tip-diffuser 24 and the internal tapered surface 66 ofthe conductor tube 14 such that electrical current can be reliablytransferred from the conductor tube 14 to the contact tip-diffuser 24and heat can be efficiently transferred from the contact tip-diffuser 24to the conductor tube 14. In addition to being cooled by the shieldinggas, the contact tip-diffuser 24 can be further cooled due to theincreased contact area between the contact tip-diffuser 24 and theconductor tube 14. The increased contact area allows efficient heattransfer from the contact tip-diffuser 24 to the conductor tube 14, asopposed to threaded contact surfaces between the contact tip and thediffuser in a prior art welding gun.

Referring back to FIGS. 3 and 4, to assemble the MIG welding gun, theouter body 90, the insulator 92 and the inner body 94 are pre-assembledto form an integrated nozzle 22 and the contact tip-diffuser 24 isinserted into the nozzle 22 from the proximal end of the nozzle 22 untilthe external shoulder 52 of the contact tip-diffuser 24 contacts theangled surface 106 of the internal distal flange 96 of the inner body94. The internal distal flange 96 prevents the contact tip-diffuser 24from further moving distally.

Next, the distal end portion 26 of the conductor tube 14 is insertedinto the proximal end of the nozzle 22 until the distal end portion 26of the conductor tube 14 is inserted into the space between the externalcontact surface 64 of the contact tip-diffuser 24 and the innerperipheral contact surface 108 of the inner body 94. No tool is requiredto connect the conductor tube 14 to the consumable assembly 16 thatincludes the nozzle 22 and the contact tip-diffuser 24. No threadedconnection is needed for secured connection. The contact tip-diffuser24, the nozzle 22 and the conductor tube 14 can be assembled by simplypressing these components toward one another. Accordingly, manufacturingcosts can be reduced.

While not shown in these drawings, the conductor tube 14 can be securedto the inner body 94 of the nozzle 22 through threaded connection asillustrated in other embodiments.

Referring to FIG. 15, in operation, a shielding gas is directed from theinternal passageway 30 of the conductor tube 14 and enters the internalcavity 38 of the contact tip-diffuser 24. The shielding gas is thendirected outside the contact tip-diffuser 24 through the plurality ofapertures 54. The apertures 54 diffuse the shielding gas and providecooling to the integrated tip-diffuser 24.

A welding wire 20 is directed from the conductor tube 14, through theinternal cavity 38 of the contact tip-diffuser 24 to the exit orifice 40of the contact tip-diffuser 24. Electrical current is transferred fromthe conductor tube 14, through the contact tip-diffuser 24, to thewelding wire 20. The radiused inlet 60 of the exit orifice 40 reducesscraping and shaving of the welding wire. The exit orifice 40 providescontact for the welding wire 20. The nozzle 22, which is disposed aroundthe contact tip-diffuser 24, protects the contact tip-diffuser 22 fromcontacting the workpiece, which is grounded and also channels theshielding gas to the welding puddle.

The contact tip-diffuser 24 with the integrated structure can besufficiently cooled due to increased contact surfaces between thecontact tip-diffuser 24 and the conductor tube 14 and due to thermalconduction from the contact tip-diffuser 24 to the shielding gas. Also,the shielding gas provides cooling both inside and outside the contacttip-diffuser 24. With sufficient cooling, the contact tip-diffuser 24can be formed of a hollow structure using less copper alloy to reducemanufacturing costs and can be used for heavy-duty applications (e.g.,high amperage operation).

Moreover, the contact tip-diffuser 24 with the hollow and integratedstructure is relatively easy to manufacture. The contact tip-diffuser 24can be formed by a forming process, including but not limited to,forging, swaging, cold forming, extruding, metal injection molding(MIM), casting, and machining. The integrated contact tip-diffuser 24which functions as both a contact tip for transferring electricalcurrent and a diffuser for diffusing a shielding gas reduces totalmanufacturing costs by eliminating a separate component for a gasdiffuser.

Referring to FIG. 16, a consumable assembly 120 and a conductor tube 126for use in the arc welding apparatus 10 and constructed in accordancewith a second embodiment of the present disclosure are shown. Theconsumable assembly 120 includes a contact tip 122 and a nozzle 124. Thecontact tip 120 in the present embodiment has a structure similar tothat of the contact tip-diffuser 24 of FIG. 15, except that the contacttip 120 of FIG. 16 does not have any aperture extending through theouter wall 50 of the contact tip 120 to diffuse gas. Instead, theapertures for diffusing shielding gas are formed in the conductor tube126.

Similarly, the contact tip 120 includes an internal cavity 38 and anexit orifice 40. A radiused inlet 60 is formed at a distal end 47 of theinternal cavity 38. The internal cavity 38 is aligned with an internalpassageway 128 of the conductor tube 126 to receive a conduit liner 32(shown in FIG. 2). The structure of the contact tip 120 is similar tothat the contact tip-diffuser 24 of FIG. 15 and the description thereofshould be considered similar hereinafter to avoid redundancy.

The conductor tube 126 includes a distal end portion 130 having aninternal tapered surface 132 for contacting an external contact surface134 of the contact tip 122. The internal tapered surface 132 and theexternal contact surface 134 improve electric current transfer and heattransfer between the conductor tube 126 and the contact tip 122. Theconnection among the contact tip 122, the conductor tube 128 and thenozzle 124 is similar to the connection among the contact tip-diffuser24, the conductor tube 14 and the nozzle 12 of FIG. 15 and thus thedetailed description thereof should be considered similar hereinafter toavoid redundancy.

The distal end portion 130 of the conductor tube 126 defines a pluralityof apertures 136 extending through the cylindrical wall 138 of thedistal end portion 130. While the plurality of apertures 136 are shownto be oriented in a radial direction of the conductor tube 126, theapertures 136 may be oriented at an angle relative to the longitudinalaxis of the conductor tube 126 or has a portion parallel to thelongitudinal axis of the conductor tube 126. The plurality of apertures136 are in fluid communication with the internal passageway 128 of theconductor tube 126. The plurality of apertures 136 are providesproximally from the proximal end portion 44 of the contact tip 122.

The contact tip 122, a nozzle 124 and the conductor tube 126 aresuitable for light-duty application (approximately 250 A and below) byforming the apertures 136 in the conductor tube 126. When the shieldinggas is directed from a gas source, through the welding cable 18 (shownin FIG. 1), and to the distal end portion 130 of the conductor tube 126,the shielding gas can be further directed outside the conductor tube 126and into a first gas chamber 140 between the nozzle 124 and the distalend portion 130 of the conductor tube 126. The first gas chamber 140 isin fluid communication with a second gas chamber 142 between the contacttip 122 and the nozzle 124. The shielding gas may be further directeddistally to the second gas chamber 142 through vent holes (not shown)formed in the internal distal flange 96 of the nozzle 124 or throughgaps (not shown) between the internal distal flange 96 and the contacttip 122. A blanket of shielding gas is thus formed around the contacttip 122 to protect the molten metal pool.

The plurality of apertures 136 may be formed proximate the interfacebetween the conductor tube 126 and the contact tip 122. Therefore, theshielding gas flowing through the apertures 136 may provide sufficientcooling to the contact tip 122 that is subjected to high heat duringoperation.

Like the contact tip-diffuser 24 of the first embodiment, the contacttip 122 is directly secured to the distal end portion 130 of theconductor tube 126 without any intervening component. In addition totransferring gas and electric current to the contact tip 122, theconductor tube 126 also functions to diffuse shielding gas to form ablanket of shielding gas around the contact tip 122. No separate gasdiffuser is needed. Accordingly, the arc welding apparatus 10 thatincludes the consumable assembly 120 and the conductor tube 126constructed in accordance with the teachings of the present disclosurehas fewer components and thus the manufacturing costs are reduced.

While not shown in the drawings, it is understood that the apertures canbe formed in both the conductor tube 126 and the contact tip 122 suchthat both conductor tube 126 and the contact tip 122 can diffuse theshielding gas. When the apertures are formed in both the conductor tube126 and the contact tip 122, the consumable assembly and the conductortube are suitable for heavy-duty applications.

Referring to FIGS. 17 and 18, a consumable assembly 202 and a conductortube 204 for use in the arc welding apparatus 10 and constructed inaccordance with a third embodiment of the present disclosure is shown.The consumable assembly 202 includes a contact tip 206 and a nozzle 207surrounding the contact tip 206. As in the second embodiment shown inFIG. 16, apertures 130 for directing shielding gas are formed in theconductor tube 204.

As clearly shown in FIG. 18, the contact tip 206 is a stub tip and has adistal end portion 214 defining an elongated exit orifice 216 and aproximal end portion 218 defining an internal cavity 220. The elongatedexit orifice 216 has a length close to the length of the internal cavity220, as opposed to the contact tip-diffuser and the contact tip in thefirst and second embodiments, where the elongated exit orifice may bemuch shorter than the internal cavity. Similar to the contacttip-diffusers 24, 68, 69, 72 of the first embodiment and the contact tip122 of the second embodiment, the contact tip 206 of the presentembodiment may have an external shoulder 240 and a tapered contactsurface 219 at the proximal end portion 218.

The nozzle 207 includes an inner body 208, an outer body 210 surroundingthe inner body 208, and an insulator 212 disposed therebetween. Theinner body 208 of the nozzle 207 includes an enlarged proximal portion222 and a narrowed distal portion 214. The insulator 212 is disposedbetween the outer body 210 and the enlarged proximal portion 222 of theinner body 208. The narrowed distal portion 214 includes an internaldistal flange 244 for engaging the external shoulder 240 of the contacttip 206 and a plurality of apertures 226 for diffusing shielding gas.While two apertures 226 are shown in FIGS. 17 and 18, any number(including one) of apertures 226 can be formed in the inner body 224. Agas chamber 228 is defined between the narrowed distal portion 214 ofthe inner body 208 and the outer body 210 and is in fluid communicationwith the apertures 226 of the inner body 208.

The conductor tube 204 includes a distal portion 230 and an engagingportion 232 disposed proximally of the distal portion 230. The distalportion 230 defines a plurality of apertures 234 in fluid communicationwith the apertures 226 of the inner body 208. The distal portion 230further defines an internal tapered surface 235 for contacting theexternal tapered surface 219 of the contact tip 206. The engagingportion 232 may includes a plurality of cam lock connection parts 236for securing the conductor tube 204 in the nozzle 202. For example,three cam lock connection parts 236 may be provided along thecircumference of the engaging portion 232 at 120° apart. The cam lockconnection parts 236 each having opposing ends 250, 252 along thecircumference of the conductor tube 204. One end 250 has a firstthickness greater than a second thickness of the other end 252 such thata tapered surface 254 is formed between the opposing ends 250, 252. Thecam lock connection parts 236 allow the conductor tube 204 to be securedinside the nozzle 207 in a sliding manner.

While not shown in the drawings, it is understood that the engagingportion 232 may be provided with threads for threaded connection withthe inner body 208 of the nozzle 208 threaded connection as illustratedin other embodiments.

When the conductor tube 204 is inserted into the nozzle 207, the camlock connection parts 236 engage an inner surface 238 of the enlargedproximal portion 222 of the inner body 208. Moreover, the distal portion230 of the conductor tube 204 engages the inner surface 240 of thenarrowed distal portion 224. When the conductor tube 204 is positionedin place, the apertures 230 of the conductor tube are aligned radiallywith the apertures 226 of the inner body 208 and the outer taperedsurface 219 is in close contact with the internal tapered contactsurface 235 of the conductor tube 204. The internal and external taperedcontact surfaces 219 and 235 improve heat transfer from the contact tip206 to the conductor tube 204, thereby providing more efficient coolingto the contact tip 206. By forming the apertures in the conductor tube204, the consumable assembly 202 and the conductor tube 204 are suitablefor light-duty applications.

Referring to FIGS. 19A and 19B, the conductor tube 204 demonstrated inFIGS. 17 and 18 is shown in different variations still in accordancewith the third embodiment of the present disclosure. FIG. 19Ademonstrates an example of a conductor tube 260 variation. In thisvariation, the plurality of apertures 234 is formed as a plurality ofslots 262. In yet another example, FIG. 19B demonstrates a conductortube 264 having a plurality of slots 266 and a plurality of holes 268.The conductor tubes 260 and 264 shown in FIGS. 19A and 19B may haveother variations similar to those demonstrated in FIGS. 9 to 13 similarto the contact tip diffusers to alter the dispersion and improve thecoverage of shielding gas.

FIGS. 20A and 20B refer back to the consumable assembly 202 and theconductor tube 204 constructed in accordance with the third embodimentof the present disclosure, and further disclose an alignment device 270.The alignment device serves as a guide to center a conduit liner (notshown) similar to the conduit liner 32 introduced in FIGS. 2 to 4 withinthe internal passageway 128 inside the conductor tube 204 and along alongitudinal axis 272. The alignment device 270 positions the conduitliner and accordingly the wire such that the portion extending into theinternal cavity 220 of the contact tip 206 is aligned with the elongatedexit orifice 216 along the longitudinal axis 272.

The addition of the alignment device 270 to the third embodiment resultsin the conduit liner extending into the internal cavity 220 from aninternal passage 274. The internal passage defines an internal taperedsurface 276 disposed centrally in the alignment device 270. Thealignment device 270 provides for the welding wire fed through theconduit liner to consistently enter a radiused inlet 60 and feed outwardthrough the exit orifice 216. The alignment device improves operation ofthe arc welding apparatus 10 by reducing inconsistencies in feeding thewelding wire through the contact tip 206.

The alignment device 270 further comprises a press fit surface 278 beingpressed into the distal end portion 130 of the conductor tube 204 in apress fit cavity 280. The press fit surface 274 is shown having achamfer 282 disposed around a proximal end 284 for ease of manufacturewhen being pressed into the distal end portion 130 of the conductor tube204 and abutting the press fit cavity 276.

Referring to FIGS. 21A and 21B, the inner body 204 demonstrated in FIGS.17 and 18 is shown in a different variation similar to the thirdembodiment of the present disclosure. An adaptor sleeve 286 having aninternal cavity 288 defining cam lock parts 290 attaches to theconductor tube 204 of the third embodiment. The adaptor sleeve 206further comprises a plurality of apertures 292 extending from an outersurface 294 to the internal cavity 288 and a plurality of threads 296disposed around the outer surface for attachment to a nozzle (not shown)assembly similar to the nozzle 207 disclosed in the third embodiment. Inthe instant example the inner body 208 of the nozzle 207 attaches to theplurality of threads 296 and comprises an internal distal flange (notshown) to secure the contact tip 206 in conformity with the teachings ofthe disclosure.

Referring to FIG. 22, a consumable assembly 302 and a conductor tube 304for use in the arc welding apparatus 10 of FIG. 1 and constructed inaccordance with a fourth embodiment of the present disclosure are shown.The consumable assembly 302 includes a nozzle 306 and a contacttip-diffuser 308. A conduit liner 310 extends longitudinally through theconductor tube 304. The contact tip-diffuser 308 includes apertures 312for diffusing shielding gas from inside the contact tip-diffuser 308 tooutside of the contact tip-diffuser 308 and thus functions as both acontact tip and a gas diffuser in the present embodiment. The contacttip-diffuser 308 is structurally similar to the contact tip-diffuser 24of FIG. 5 except that the proximal end portion 314 of the contacttip-diffuser 308 includes a spherical contact surface 316. Likereference numbers will be used for like parts as such these parts mayfunction in a similar manner as previously described in thisapplication.

As clearly shown in FIG. 23, the contact tip-diffuser 308 includes aproximal end portion 314 defining an internal cavity 38 and a distal endportion 46 defining an elongated exit orifice 40. The proximal endportion 314 includes an external shoulder 52 and a spherical contactsurface 316. Similarly, the contact tip-diffuser 308 has a plurality ofapertures 54 extending radially through the proximal end portion 314 todiffuse shielding gas. Therefore, the consumable assembly 302 issuitable for heavy-duty (e.g., high amperage) welding operation.

The nozzle 306 has a structure similar to that the nozzle in FIG. 15.Like reference numbers are used for like parts and thus the descriptionand the description thereof should be considered similar hereinafter toavoid redundancy.

The conductor tube 304 of the present embodiment is structurally similarto the conductor tube of FIG. 15, except that the conductor tube 304defines a spherical contact surface 324 corresponding to the sphericalcontact surface 316 of the contact tip-diffuser 308. The sphericalcontacts surfaces 316 and 324 of the contact tip-diffuser 308 and theconductor tube 304 improve engagement between the tip/diffuser 308 andthe conductor tube 304.

Referring to FIGS. 23 to 25, a consumable assembly 402 and a conductortube 404 for use in the arc welding apparatus 10 of FIG. 1 andconstructed in accordance with a fifth embodiment of the presentdisclosure are shown. The consumable assembly 402 includes a contacttip-diffuser 404 and a nozzle 406. The contact tip-diffuser 404 issimilar to the contact tip-diffuser 308 of FIGS. 15 to 16 except thatthe contact tip-diffuser 308 has an annular groove 408 formed in thespherical contact surface 316. Like reference numbers are used for likeparts as such these parts may function in a similar manner as previouslydescribed in this application.

Similarly, the contact tip-diffuser 308 of the present disclosure has aproximal end portion 314 and a distal end portion 46. The proximal endportion 314 has an external shoulder 52 and a spherical contact surface316. An annular groove 418 is formed along the circumference of thespherical contact surface 316.

As shown in FIG. 25, when contact-tip diffuser 308 and the conductortube 404 are secured inside the nozzle 406, the spherical contactsurface 316 of the contact tip-diffuser 404 is in close contact with thespherical contact surface 324 of the conductor tube 404. The annulargroove 408 prevents possible locking of the contact tip-diffuser 404 tothe conductor tube 404 due to thermal expansion of the spherical contactsurfaces 316 and 324.

Referring to FIGS. 26 and 27, a consumable assembly 402 and a conductortube 404 for used in the arc welding apparatus 10 of FIG. 1 andconstructed in accordance with a sixth embodiment of the presentdisclosure is shown. The consumable assembly 402 includes a contact tip406 and a nozzle assembly 408. The contact tip 406 is similar to thecontact tip 122 in FIG. 16 and includes an external contact surface 407that is tapered outwardly from the proximal end portion to the distalend portion.

The nozzle assembly 408 includes a nozzle housing 410 and a nozzle cup412 mounted around a distal end 413 of the nozzle housing 410. Thenozzle cup 412 may be assembled to the nozzle housing 410 throughthreaded connection, or quick disconnects, among other types ofconnections. The nozzle housing 410 includes an outer body 414, an innerbody 416 and an insulator 418 disposed between the outer body 414 andthe inner body 416. The inner body 414 functions as a tip holder forsecuring the contact tip 122.

The conductor tube 404 includes a distal end portion 420 having aninternal contact surface 422 and an external connecting surface 423. Thedistal end portion 420 may be formed separately and molded to the mainbody of the conductor tube 404. Alternatively, the distal end portion420 may be an integral part of the conductor tube 404. The internalcontact surface 422 is tapered to match the external contact surface 407of the contact tip 406. The external connecting surface 423 may havethreads for threaded connection with the inner body 416 of the nozzleassembly 408. A plurality of apertures 424 extend through the internalcontact surface 422. When the conductor tube 404 engages the contact tip406, the internal tapered contact surface 422 of the conductor tube 404is in close contact with the external tapered contact surface 407. Theimproved contact between the conductor tube 404 and the contact tip 406improves heat transfer from the contact tip 406 to the conductor tube404.

FIGS. 28 to 30 refer to a consumable assembly 450 and a conductor tube452 for use in the arc welding apparatus 10 of FIG. 1 and constructed inaccordance with a seventh embodiment of the present disclosure.Referring to FIG. 28, a consumable assembly 450 is similar to theconsumable assembly 16 of the first embodiment and as such these partsmay function in a similar manner as previously described in thisapplication. A nozzle assembly 452 attaches to a conductor tube 454through an intermediate connection in the form of a sleeve 456 and anengaging portion 458 comprising a plurality of threads 460. The instantimplementations additionally incorporates an alignment device 462disposed in the conductor tube 454 to align a conduit liner with acontact diffuser tip 464. This embodiment provides for an alternativemeans of connecting the disposable assembly 450 to the conductor tube454 with an added benefit of a replaceable sleeve 456 to allow forreplacement of the plurality of threads 460 without replacing theconductor tube 454.

The sleeve 456 engages the distal end 466 of the conductor tube 454. Aninner surface profile 468 of the sleeve 456 is configured to slide overan external surface profile 470 of the conductor tube 454. The sleeve456 is further held in position by a locking ring 472 disposed in anannular groove 474. The engaging portion 458 of the sleeve 456 comprisesthe plurality of threads 460 that connects to an inner body portion 476of the nozzle assembly 452 also comprising a plurality of threads 478.

Still referring to FIG. 28, the alignment device 462 serves to center aconduit liner (not shown) similar to the conduit liner 310 introduced inFIG. 20 within an internal passageway 480 inside the conductor tube 454along a longitudinal axis 482. The alignment device 462 positions theconduit liner such that the portion extending into the internal cavity484 of the contact tip diffuser 464 is aligned with the exit orifice 486along the longitudinal axis 482. The addition of alignment device 462 tothis embodiment results in the conduit liner extending into the internalcavity 484 providing for the welding wire fed through the conduit linerto consistently enter a radiused inlet 488 and be fed out through theexit orifice 486.

Another feature of the alignment device 462 disclosed in the seventhembodiment is a plurality of ports 490 bordering on an internal passage492. The conduit liner is disposed in the internal passage 492 to alignthe conduit liner with the internal cavity 484 of the contact tipdiffuser 464 and the plurality of ports 490 provides increasedcross-sectional area within the conductor tube 454. The increasedcross-sectional area ensures that the alignment device 462 does notrestrict the flow of shielding gas through the conductor tube 454.

Referring now to FIG. 29, the alignment device 462 comprises a press fitsurface 502 is pressed into the distal end 466 of the conductor tube 454into a press fit cavity 504. The distal end 466 of the conductor tube454 further defines an external surface profile 506 that issignificantly circular having a radial alignment mechanism such as aflat, tab, keyed-slot, or groove. In this example a flat 508 is disposedon two opposing sides for radial alignment. The inner profile 468 of thesleeve 456 is configured to slidably engage the external surface profile508 such that the sleeve 456 can slide along the longitudinal axis 482,but is restricted from rotating around the conductor tube 454. Finally,to restrict motion along the longitudinal axis, the locking ring 472 isdisposed in the annular groove 474. With the locking ring 472 in place,the sleeve 456 is sufficiently restrained. The contact tip diffuser 464engages the distal end 466 of the conductor tube 454 and the inner body476 of the nozzle assembly 452 connects to the engaging portion 458 ofthe sleeve 456 through the mating surfaces of each of the plurality ofthreads 460 and 478.

The assembly of the instant embodiment of the welding apparatus isfurther detailed in an assembled, cross-sectional view shown in FIG. 30with only the inner body 476 of the nozzle assembly 452 shown forclarity. To retain the position of the contact tip diffuser, the innerbody 476 further defines an internal distal flange 520 that abuts anexternal shoulder 522 of the contact tip diffuser 464 and retains theposition of the contact tip diffuser 464. The engaging portion 458 ofthe sleeve 456 defined as the plurality of threads 460 is clearly shownengaging the plurality of threads 478 of the inner body 476. Further,the press fit cavity 504 of the conductor tube is shown to demonstratethe press fit surface 502 of the alignment device 462 assembledaccording to the instant embodiment.

Still in accordance with the seventh embodiment of the disclosure FIG.31A illustrates the connection of the sleeve 456 and the conductor tube454. The external surface profile 506 at the distal end 466 of theconductor tube 454 comprises a flat 508 on two opposing sides. The innersurface profile 468 of the sleeve 456 is configured to slidably engagethe external surface profile 508 such that the sleeve 456 can slidealong the longitudinal axis 482, but is restricted from rotating aroundthe conductor tube 454. The engaging portion 458 and the plurality ofthreads 460 are also shown in FIG. 31A to provide further detail.

Similar to the seventh embodiment of the disclosure and relating back tothe aforementioned embodiments, a different variation of a sleeve 550and a conductor tube 552 are shown in FIG. 31B. In this example anexternal surface profile 554 of the conductor tube is defined as havinga key slot 556 and a key 558 to engage an inner surface profile 560 ofthe sleeve 550. In the instant example, the sleeve 550 engages thedistal end 562 of the conductor tube 552 and is restricted from rotationabout the conductor tube 552 with the key 558 disposed in the key slot556 and in the inner surface profile 560 of the sleeve 550. Theconductor tube 552 may similarly be configured to engage an innersurface profile of a sleeve through a spline coupling. Further theengaging portion 564 of the sleeve 550 is defined as cam lock parts 566.Similar to the first embodiment, the cam lock parts 566 engage an innerbody of a nozzle assembly (not shown) rather than the plurality ofthreads 460 in the consumable assembly of the seventh embodiment.

In yet another implementation of the seventh embodiment of thedisclosure and relating back to the aforementioned embodiments, adifferent variation of a conductor tube 568 and a sleeve 570 are shownin FIG. 32. This variation is similar to that disclosed in FIG. 31A, butincludes a set screw 572 as a means of securing the sleeve 570 to theconductor tube 568. The set screw 572 is disposed in a hole 574 in thesleeve 570 and a threaded hole 576 in the conductor tube 568 to securethe sleeve 570 to the conductor tube 568. This implementation mayfurther include the sleeve 570 having an elongated surface 578 thatextends at least to the distal end 466 of the conductor tube 568 whenassembled. The instant implementation applies the sleeve 570 to protectthe distal end 466 of the conductor tube 568 from wear and protect thedistal end 466 from impact.

Referring back to the seventh embodiment introduced in FIG. 28, FIG. 33Aillustrates the alignment device 462. The plurality of ports 490 isclearly depicted as being evenly spaced around and bordering theinternal passage 492. The even spacing of the plurality of ports allowsfor consistent passage of shielding gas through alignment device 462.Further, the press fit surface 502 is shown having a chamfer 602disposed in a proximal end 604 for ease of manufacture when beingpressed into the distal end 466 of the conductor tube 454 and abuttingthe press fit cavity 504.

Referring now to FIGS. 33B and 33C, different variations of thealignment device 462 similar to seventh embodiment are shown providingalternate embodiments that can be incorporated from the aforementionedteachings of this disclosure. The alignment device 606 shown in FIG. 33Bhas a plurality of ports 608 disposed within the wall 610 of thealignment device 606. Further, instead of having a press fit surface 502as disclosed in the seventh embodiment, the instant example has as anouter surface 612 defining a plurality of threads 614 configured toconnect to a threaded surface disposed in a conductor tube.

The alignment device 616 shown in FIG. 33B has a plurality of ports 618such that when the alignment device 616 is disposed in a conductor tube(not shown), the plurality of ports 618 border an interior surface 619(shown as a dotted line) of the conductor tube. Further, an outersurface 620 is disposed around the alignment device 616 and comprisescam lock parts 622. In this example, the interior surface of theconductor tube further defines an engaging portion configured to engagethe cam lock parts 622 and retain the alignment device 616.

The description of each embodiment may discuss certain features that areoptional. In addition, it is contemplated herein that distinct featuresof one implementation may be used in combination with distinct featuresof other implementations. The previous examples are not suggested tolimit other variations and are presented to teach possible embodimentsof this disclosure.

The present disclosure is merely exemplary in nature and, thus,variations that do not depart from the spirit of the disclosure areintended to be within the scope of the present disclosure. Suchvariations are not to be regarded as a departure from the scopecontemplated in the present disclosure.

What is claimed is:
 1. An arc welding apparatus comprising: a conductortube defining an internal passageway and a distal end portion, theinternal passageway having an internal profile proximate the distal endportion; an alignment device comprising an exterior profile and aninternal passage, the exterior profile being configured for mechanicalattachment to the internal profile of the conductor tube, the internalpassage having a tapered profile whereby a diameter of the internalpassage at a proximal end portion is larger than a diameter of theinternal passage at a distal end portion, and wherein the exteriorprofile of the alignment device includes a plurality of cam lockingparts separated one from another by a gas port extending from theproximal end portion to the distal end portion of the alignment device,wherein the internal profile of the conductor tube includes an engagingportion configured to engage one or more of the plurality of cam lockingparts to retain the alignment device within the conductor tube; and aconduit liner disposed in the internal passageway of the conductor tubeand the alignment device and terminating proximate the distal end of theconductor tube.
 2. The arc welding apparatus of claim 1, wherein thealignment device comprises a plurality of ports for the passage of a gasthrough the conductor tube.
 3. The arc welding apparatus of claim 2,wherein the plurality of ports extend from the proximal end portion tothe distal end portion of the alignment device.
 4. The arc weldingapparatus of claim 2, wherein the plurality of ports are evenly spacedradially about the alignment device.
 5. The arc welding apparatus ofclaim 1, wherein the internal profile of the conductor tube isconfigured for accepting the exterior profile of the alignment device,and the conductor tube and the alignment device are press fit together.6. The arc welding apparatus of claim 1, wherein the boundaries of theinternal passage and exterior profile of the alignment device areconcentric.
 7. The arc welding apparatus of claim 1, wherein thealignment device aligns the conductor tube with the longitudinal axis ofthe conductor tube.
 8. The arc welding apparatus of claim 1, furthercomprising a contact tip having an internal cavity, a proximal end, anda distal end, the proximal end engaging the distal end of the conductortube and the distal end defining an exit orifice.
 9. The arc weldingapparatus of claim 8, wherein the alignment device aligns the conduitliner with the exit orifice of the contact tip along the longitudinalaxis of the conductor tube.
 10. An arc welding apparatus comprising: aconductor tube defining an internal passageway and a distal end, theinternal passageway having an internal profile; and an alignment devicehaving a proximal end, distal end, an exterior profile and an internalpassage, the exterior profile being configured for mechanical attachmentto the internal profile of the conductor tube and the internal passageconfigured for alignment of a conduit liner, wherein the internalpassage has a tapered profile whereby a diameter of the internal passageat a proximal end portion is larger than a diameter of the internalpassage at a distal end portion, wherein the exterior profile of thealignment device includes a plurality of cam locking parts separated onefrom another by a gas port extending from the proximal end portion tothe distal end portion of the alignment device, wherein the internalprofile of the conductor tube includes an engaging portion configured toengage one or more of the plurality of cam locking parts to retain thealignment device within the conductor tube.
 11. The arc weldingapparatus of claim 10, further comprising a conduit liner disposed inthe conductor tube internal passageway passing through the internalpassage of the conduit liner and terminating proximate to the distal endof the conductor tube.
 12. The arc welding device of claim 10, whereinthe conductor tube internal profile is press fit to the exterior profileof the alignment device.
 13. The arc welding device of claim 10, whereinthe conductor tube internal profile defines an annular groove forlocking the alignment device.
 14. The arc welding device of claim 10,wherein the conductor tube internal profile defines a plurality ofthreads for mechanically attaching the alignment device comprising aplurality of threads.
 15. The arc welding device of claim 10, whereinthe alignment device has at least one port extending from the proximalend to the distal end.
 16. The arc welding device of claim 15, whereinthe at least one port defines at least one passage bordering theinternal profile of the conductor tube.
 17. The arc welding device ofclaim 15, the at least one port being rounded in shape.
 18. The arcwelding device of claim 15, the at least one port being polygonal inshape.
 19. The arc welding device of claim 15, wherein the at least oneport is aligned with a proximodistal axis of the alignment device. 20.The arc welding device of claim 15, further comprising a plurality ofports equally spaced radially about the internal passage.
 21. Analignment device for use in a welding apparatus comprising an exteriorprofile being configured for mechanical attachment and an internalpassage, wherein the alignment device is disposed within an internalpassageway of a conductor tube and aligns a conduit liner with an exitorifice of a contact tip, wherein the internal passage has a taperedprofile whereby a diameter of the internal passage at a proximal endportion is larger than a diameter of the internal passage at a distalend portion, and wherein the exterior profile of the alignment deviceincludes a plurality of cam locking parts separated one from another bya gas port extending from the proximal end portion to the distal endportion of the alignment device, wherein the internal profile of theconductor tube includes an engaging portion configured to engage one ormore of the plurality of cam locking parts to retain the alignmentdevice within the conductor tube.
 22. The alignment device of claim 21wherein, the exterior profile of the alignment device is configured toabut an internal profile of the conductor tube.
 23. The alignment deviceof claim 22, wherein the interior profile of the conductor tube isconfigured for accepting the exterior profile of the alignment device,and the conductor tube and the alignment device are press fit together.24. The alignment device of claim 21, the gas port extending from aproximal end to a distal end.
 25. The arc welding device of claim 21,the gas port being rounded in shape.